1. Field of the Invention
The present invention relates to a method of manufacturing a pneumatic tire whose rubber components are formed by winding a unvulcanized rubber tape.
2. Description of the Related Art
Conventionally, unvulcanized rubber tires are made of unvulcanized rubber components having various shapes and sizes. As the unvulcanized rubber components are formed by extruders, the number and sizes of the extruders are depend on the maximum size and the number of the kinds of the rubber components. Usually, at least several extruders which are relatively large-sized are required.
In recent years, in order to decrease the number and size of extruders to decrease the plant size and to establish a flexible manufacturing system, it was proposed to make a pneumatic tire by winding an unvulcanized rubber tape around a drum directly or indirectly thereon instead of applying a rubber component. In this method, as shown in FIG. 11, an unvulcanized rubber tape T is wound into a target cross sectional shape similar to the final shape of the rubber component by controlling the overlaps of the windings of the tape.
Therefore, it became possible to make rubber components having various shapes and sizes.
In general, different rubber components of a tire are usually made of different rubber compounds. If the method of making a rubber component is simply changed from the extruding into a final shape to the winding into a final shape, it is still necessary to prepare various unvulcanized rubber tapes made of different rubber compounds.